Recent content by pukb

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    Deflection in a Simply supported beam

    Cross section: Thickness = 2mm height = 50 mm
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    Deflection in a Simply supported beam

    Hi All As shown in the attached image, I have a simply supported beam with a load of 150kN acting at the center of the beam span. E = 210 GPa rho = 7800 kgm-3 span = 250 mm After solving this in FE solver, I got maximum displacement to be ~4mm (at node 52) But, on using the theoretical...
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    Crush vs. Crash Analysis: What's the Difference?

    What is the difference between crush and crash analysis. I understand that, crush analysis is much a static analysis unlike crash analysis which is a dynamic analysis. What I am looking at is the results that anybody would like to get / view /understand from a crush analysis and crash...
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    How the ductility of metal change when grains is decreased ?

    You can go through the book on Material science basics by Callister. Read dislocations section. I am sorry, i do not remember full name of the book
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    Reducing Initial Time Step Benefits for FE Analysis

    Hi AlephZero Can you please give a more practical example for this.
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    Reducing Initial Time Step Benefits for FE Analysis

    The problem solved is EXPLICIT in PAMCRASH solver. Since the problem is explicit, we are not looking at frequency response. There is a provision to give a lower timestep (lower to the stable one calculated by solver) throughout the run - it is understood also, as i mentioned earlier htere is a...
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    Reducing Initial Time Step Benefits for FE Analysis

    What would be the practical application of reducing the initial time step in a FE analysis. By Initial, I mean - the commercial software always calculates stable timestep based on geometry and material properties. There is always a provision given to use a lesser time step value at start of the...
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    Entropy & Work Done: Understanding Reversible Heating/Stirring

    There is a container containing water (state 1) which is being stirred. There is a temperature rise (state 2) due to stirring. It is required to find out change in entropy of the system if the process is reversible. Since, there is no heat transfer there would be no change in entropy due to...
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    Solving Exchange of Momentum by Conserving Energy & Momentum

    yes, it does apply - what i meant was the heights to which cog is lifted are not same when force is applied at center and at corner because the latter case will cause some rotation as well. The problem is to quantify that
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    Doubt Regarding Shearing Stresses In a Beam

    the surface at top and bottom are free and hence inorder to have forces balanced, on taking a small element at top of the beam ; since there are no shear stresses towards atmosphere there cannot be any shear stress inside.
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    Solving Exchange of Momentum by Conserving Energy & Momentum

    Imagine a block of wood resting on two supports at each end. You point a gun upward under the block and shoot the block upwards. One scenario is you shoot the block upwards in the exact center. Another scenario is you shoot upwards near one of the support ends. The block is thick enough that...
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    Why do we need integration points in FEA?

    Hi Why are displacements calculated on integration points but not directly over the nodes. The whole purpose of discretizing a structure in FEA is to have fewer degrees of freedom, then why add integration points when there are well defined nodes. Also, can somebody please explain having...
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    Direction of vibration of molecule with respect to transfer of heat

    That would be really difficult to answer at individual molecule/atom level for conduction. If you are looking at conduction in metals, you should be worried more about movement of electrons which forms a major part of heat transfer and molecular vibration only a little. Having said that, the...
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    Penalty and Lagrangian methods

    Hi Can somebody please explain fundamentally what is the difference between these two methods of modelling contact interfaces? I would prefer a more qualitative explanation (physics concept based ) rather than a more mathematical description.
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    How do element normals impact FE mesh analysis results?

    it is a coupled analysis involving structural (explicit and implicit) and thermal analysis (implicit)
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